Experimental Study on the Acid Fracturing Fracture Propagation Law of a Fractured Carbonate Reservoir in the Majiagou Formation

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

RE:  Experimental study on acid fracturing fracture propagation law 2 of fractured carbonate reservoir in Majiagou Formation

This manuscript is well-written and of high quality. The continuity of the written material is acceptable. I recommend this manuscript for acceptance for publication in the Journal. However, it needs some minor revisions before acceptance as follows:

1-      The Captions (explanations) below the figures, especially Figures 3, 4, 5 and 6, are written very briefly. Especially in the figures shown with the letters a, b and c, it is better to write separate explanations for each so that the reader can make the necessary inferences from the relevant figure without referring to the text.

2-       2- The references at the end of the manuscript should be checked carefully and written according to the journal format.

3-      3- I think the number of references used for the manuscript is low. 20 references is not enough for an ISI article. In this regard, you can refer to more material and new references in the introduction section of the manuscript.

Comments on the Quality of English Language

The Quality of English language is good.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Dear authors! Thank you for very interesting paper. You did a really good reasearch. Fracturing is used in different depths for different reservoirs and locations. With different depth there is a difference in temprature, and presented acid-fracturing fluids have given viscosity at room temperature, but what about higher temperature, how will it affect the fluids?

Now I will list some specific comments to your paper.
line 40- did you mean compaction as the process ao compact? It is a bit unclear.
lines 67-68 - what property? Is it just one property of the rock, or more of them? It’s unclear is the property weaken by degrees or? My try to rephrase it.
line 106 - In figure 1 there is no legend, what are those physical symbols representing (sigmas’)?
line 109 - what software?
lines 169-171 - here, you are mentioning three stress but you need to write the symbol for them, it would be easier to follow.
line 196 - in table 1, write what NF means, and put the -1 (flowrate) in superscript.
lines 222-227 - you can’t write it like the manual, it needs to be written in passive form.
line 222 - the experiment can’t conclude, you can based on the results of the experiment. Change the word or rephrase the sentence.
line 258 - starting from figure 3 (also figures 5, 7 and 8) it would be more logical to show the wellbore vertically (like in figure 2).
line 288 - why did you choose the crossed-linked acid for this part of the experiment? Is it because of results of the previous part? Maybe write it, just to clarify it.
line 304 - in figure 5 a, what is HF?
line 328 - you used a combination of acid fluids, in what ratio?
line 399 - how do you know about the temperature?
line 418 - same as previous.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Acid fracturing is a widely used technique in the petroleum industry to enhance hydrocarbon recovery from reservoirs. This research provides a comprehensive, experimental analysis of acid fracturing in carbonate reservoirs, with a particular focus on the Majiagou Formation. The authors conducted a series of experiments to investigate the influence of various factors, such as fluid type, injection rate, and the presence of natural fractures, on the propagation of acid-induced fractures.

1) The study makes the following key contributions: the use of a high-precision triaxial testing apparatus enabled the simulation of real subsurface conditions, providing more reliable results; a multifactorial analysis was conducted; a significant contribution to understanding the mechanisms underlying acid-induced fracture propagation, such as fluid-rock interaction, crack initiation and propagation; the study results can be used to optimize acid fracturing parameters based on the specific characteristics of each reservoir; the experimental data obtained can be used to validate and improve existing numerical models, allowing for a more accurate simulation of the acid fracturing process.

Suggestions for improvement:

2) An analysis of the impact of rock heterogeneity on fracture propagation.

3) An analysis of the extent of the damage zone around the fracture and its impact on fluid flow.

4) An analysis of the impact of in-situ stress on fracture initiation and propagation, especially in the presence of natural fractures.

5) Development of comprehensive numerical models for simulating the acid fracturing process.

 Comments on the Quality of English Language:

English writing is fluent. Language is fine.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf